Of the systems I've tried (macosx 10.3.9 w/perl 5.8.1; freebsd 5.4-STABLE/amd64 and 5.4-RC4/i386 both w/perl 5.8.6), the only one that came up with the right answer (0) was the amd64 box. Everywhere else, I got different values that are ridiculously large.

When I added "$&" to the print statement, I always got the right answer, so I would assume the problem lies with the optimization that applies when "$&" is not used.

Presumably, when perl compiles a script that does not use "$&", part of what is being optimized out involves allocating some resource that is needed to store or set @-.

(updated to make last paragraph easier to read)

Another update: after seeing davido's doubts about my conclusion, and even after replying to that, I have to admit he may have a point -- I tried one other mod to the OP script: add parens around "b" in the regex, and the problem goes away. So I'll guess that there is some logic that is invoked by the need to do a capture, or the need to handle $&, that will not be invoked when neither need arises, and (for some, maybe most, perl builds) this causes the problem with using @-. But that's just a guess, in hopes that it might help the perl source-code wonks to nail this thing.

In reply to Re: @- Bug on the loose, lets isolate it by graff
in thread @- Bug on the loose, lets isolate it by davido

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